solved What stage3 to use for Pentium 6200 (westmere)?

[kery]

Hi,

at first i wanted to build a system around the latest stage3 from the westmere build available here:
https://build.funtoo.org/next/x86-64bit/intel64-westmere/2023-01-31/

But it failed always either on chrooting into the new system from the live system with a "Illegal Instruction" exception or failed with a manually created disk (copy stage3, create user, fstab etc.) from scratch and boot into the system from grub shell. Again here i got a kernel panic with "Atempted to kill init! exitcode=0x00000004".

For 0x00000004, i again found some "Illegal Instruction" issue (this is for ARM cpu, but i guess the kernel exception code 0x00000004 will be same for all architectures on illegal instructions):
https://stackoverflow.com/questions/54303119/kernel-panic-with-exitcode-0x00000004-after-init

I found several reports on that issue here:
https://bugs.funtoo.org/browse/FL-5730?jql=text ~ "westmere"

https://bugs.funtoo.org/browse/FL-6327

https://bugs.funtoo.org/browse/FL-5730

all have something to do with lack of instructions (eg. aes,sse4_x) on lower end cpus.

The actual westmere stage states in the build info that it is compiled with aes, sse4_x instructions. My P6200 definitly does not support it.

cpuid2cpuflags gives me this:

CPU_FLAGS_X86: mmx mmxext popcnt sse sse2 sse3 ssse3
lscpu flags info also does not include any aes or sse4_x instructions

So the question here is: What stage should i use to get best performance results on my P6200 cpu?

The last comment from drobbins here says that one should use the intel64-nehalem stage3:
https://bugs.funtoo.org/browse/FL-5730

But having a look at the flags also show aes and sse4_x flags:'
https://build.funtoo.org/next/x86-64bit/intel64-nehalem/2023-01-30/build-info.json

So the question already asked in the title is: What stage3 to use for Pentium 6200 (westmere) to get best performance results?

As a very, very new Funtoo user i didnt expect all these obstacles, but hey, if its too easy, its not fun 🙂

Thanks in advance

K.

[cardinal]

The core2 march profile is the next available stage3 that is a generation down from nehalem that excludes SSE4.1, SSE4.2, and POPCNT.

‘core2’

Intel Core 2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, CX16, SAHF and FXSR instruction set support.

Reference: https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html

Verify MMX, SSE, SSE2, SSE3, SSSE3, CX16, SAHF and FXSR would be enabled by gcc if you were using native (gcc autodetection of options supported by CPU).

gcc -c -Q -march=native --help=target | grep enabled

Reference: https://wiki.gentoo.org/wiki/GCC_optimization

If all are not enabled default to generic_64 

Edited February 24, 2023 by cardinal

[kery]

4 hours ago, cardinal said:

The core2 march profile is the next available stage3 that is a generation down from nehalem that excludes SSE4.1, SSE4.2, and POPCNT.

‘core2’

Intel Core 2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, CX16, SAHF and FXSR instruction set support.

Reference: https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html

Verify MMX, SSE, SSE2, SSE3, SSSE3, CX16, SAHF and FXSR would be enabled by gcc if you were using native (gcc autodetection of options supported by CPU).

gcc -c -Q -march=native --help=target | grep enabled

Reference: https://wiki.gentoo.org/wiki/GCC_optimization

If all are not enabled default to generic_64 

Nehalem also failed. That silent fchroot/chroot fail (ill open a bug report on it later). The Core2 march seems to meet the requirement by your gcc check. Ill give it a try now and report here.

[kery]

The Core2 stage3 works!

[kery]

15 hours ago, kery said:

The Core2 stage3 works!

...booting into gnome stage3 works without any issue. Login into session works too, but whenever i try to start something related to gnome-*, like gnome-control-center, the entire session crashes and sends me back to the login screen. Some applications work flawless, other crash entire session. As said, mostly gnome-* binaries 😞

[kery]

More on this gnome-* apps execution session crash thing (can be considered solved) here: https://bugs.funtoo.org/browse/FL-11051